Near-Optimal Power Allocation and Multiuser Scheduling with Outage Capacity Constraints Exploiting Only Channel Statistics

In this letter, we consider a delay-constrained wireless communication system where a delay constraint is characterized by the information outage probability in a transmission of K-block Rayleigh flat-fading channels. With multiple users, each given an individual delay requirement, this letter aims to minimize the total transmitted power by optimizing jointly the power distribution and the time sharing of a time-division (TD) multiuser system where the transmitter knows only the channel statistics (CST) but the mobile receivers (or users) have perfect knowledge of the channels. A suboptimal solution which utilizes Gaussian approximation with the mean and variance derived on the instantaneous mutual information and convex optimization, is proposed. Numerical results show that the proposed scheme performs nearly the same as the global optimum.